Daikin Outdoor Unit For Reverse Cycle System RY100LUY1

(1) Set operation OFF and power OFF. Disconnect the connector.

(2) Check that the voltage between the pins 3 - 4 is about 15 VDC.

(3) Check that the voltage between the pins 1 - 4 is about 5 VDC.

(4) Keep operation OFF and power OFF. Connect the connector.

(5) Check whether 2 pulses (0 and 5 VDC) are output 4 times at the pins 1 - 4 when the fan motor is rotated 1 turn by hand.

If NG in steps 2 and 3 Defective PCB

Warning: Do not touch the energized part (high voltage part) for at least 10 minutes after the power is turned OFF.

Be sure to touch the earth terminal with a hand to release static electricity from the body (to prevent PCB from being damaged).

Residual electric charge of the power transistor (should be DC 50V or less)

Remove the wire connecting the power transistor and the compressor. Remove it from the compressor terminal side. During this work, be careful not to deform. Faston terminal at the end of the relay wire.

Resistance measurement for phase 1

Resistance measurement for phase 2

Resistance measurement for phase 3

Is the resistance value equal to 5 times or more than the other resistance values?

Check for Fan Motor Connector (Signal Line)

(2) With the fan motor connector disconnected, measure the resistance between each pin, then make sure that the resistance is more than the value mentioned in the following table.

(2) With the fan motor connector disconnected, measure the resistance between each pin, then make sure that the resistance is balanced in ±30%.

Check for Fan Motor Connector (Power Supply Line)

With the relay connector disconnected, measure the resistance between UVW phases of the connector (3 cores) at the motor side, then make sure that the resistance between each phase is balanced and not short-circuited.;

Warning: High pressure checks should be performed by trained personnel only

Enter the current pressure level

Is the pressure level above the normal range?

If pressure is above normal, proceed with the following checks

Check if the condenser side is causing the high pressure

List the possible causes of high pressure

Sign off on the high pressure check

Warning: Disconnect the thermistor from the PCB before proceeding

Thermistor disconnected from the PCB

Check if the measured values correspond with the values in the table

Sign off on the thermistor check